Clean-install Windows 7 from the upgrade disc

Topping the long list of readers’ Windows 7 questions is whether you can use the upgrade disc to perform a clean-install of the new OS.

You may be surprised to discover that in Windows 7 there’s no difference between the “upgrade” and “full” DVDs and — just as with XP and Vista — the cheaper upgrade version can indeed be used to perform a clean-install.

But that’s just one of your many Windows 7 questions. From what’s possible, to what’s legal, to what-on-earth-were-they-thinking, here’s the skinny on the ins and outs of Microsoft’s best OS yet. There’s no way to fit all your Win7 queries into a single column, so you can be sure I’ll have many more Win7 FAQs in the weeks to come. Will a Win7 upgrade disc install the full OS?

“It looks like you can use the upgrade version of Windows 7 to install a ‘genuine’ copy of Windows 7 on any PC, whether it already has Windows on it or not. Why would anybody pay way more money and buy a full-install version of Windows 7 instead of an upgrade version?”

Good question. So far, the only people I know who’ve paid for the full version of Windows 7 thought they had to buy it because they were running Windows XP. When they read that they couldn’t do an in-place upgrade from XP to Win7, they mistakenly thought they had to buy the full release. They got ripped off.

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The terminology stinks, but as you will see below in my discussion of upgrade pricing, almost everybody qualifies for an upgrade version of Windows 7.

In my experience, most people using the upgrade package find that their new Win7 key validates immediately after the PC connects to the Internet. You can maximize your chances of getting instant gratification (validation), however.

If you have a version of Windows running on your PC, start Windows, insert the Windows 7 upgrade DVD, and follow the on-screen instructions. (All of the usual caveats about first backing up your data apply, of course.) If you wish, you can reformat your hard drive at the beginning of the installation process. This wipes out all the old data stored on the drive.

In my testing, as long as I started the Win7 installation from within Windows, the upgrade key passed validation. It didn’t matter, in my test runs, whether the PC’s previous version of Windows had ever been validated as “genuine” or not.

If you don’t have Windows running — for example, if you’re installing the OS on a new hard drive — boot from the Win7 upgrade DVD and follow the on-screen instructions. Chances are good that Windows 7 will validate immediately, even if there was no copy of Windows on the drive beforehand.

I have a theory about how and why this straightforward validation just works, but Microsoft hasn’t yet divulged details. I’ll revisit the whys and wherefores in a future column.

If you type in the validation key and see a message stating, “The product key is not valid,” don’t fret. Go ahead and install Win7 without the key and plan on activating the OS later. Remember that you can run Win7 up to 120 days without activating it, as I explained in my Aug. 20 Top Story. How do I get the upgrade key to activate?

“I installed the Windows 7 upgrade and the key doesn’t work. What should I do next?”

In such situations, Microsoft recommends that you call the company to validate your copy of Win7 over the phone. In my experience, phone validation works quickly and easily. The people answering the phone bend over backwards to get Win7 validated.

If you want to try this official, phone-it-in approach, review the question in the next section and make sure your PC qualifies for upgrade pricing. If it does, but you can’t get the key to work, gather whatever information you need to verify you qualify and then call Microsoft. The easy way to get Microsoft’s Win7 activation phone number is to click Start, type slui 4, and press Enter.

That said, you can activate with an upgrade key without calling Microsoft at all. There are several ways to do so. For example, writer Paul Thurrott documents in a blog post how you can upgrade in this situation by changing a byte in the Registry and running a single command line.

Failing that, another fairly simple (if more time-consuming) activation method to install from the Win7 upgrade disc and then upgrade Win7 on top of itself. This technique works in Win7 in a nearly identical way to the trick WS editorial director Brian Livingston described for Vista in a Feb. 1, 2007 Top Story.

The short version of that trick is this: Once you’ve installed Win7 from the upgrade DVD, start Win7, and then stick the upgrade disc in the drive again. Follow the instructions to upgrade, but don’t choose Custom — you’re upgrading to Windows 7 from Windows 7. Enter the key when requested, and it’ll validate the next time you’re online. Does my PC qualify for upgrade pricing?

“I understand that there are many different ways to upgrade a PC to Windows 7. The $64 question (give or take a few bucks) is whether my PC qualifies for the Upgrade Option for Windows 7 rather than my having to buy the full version. How can I tell?”

Microsoft made it easy in Windows 7 to perform a full install of Windows 7 using only the less-expensive Upgrade Option for Windows 7. In fact, MS made the trick even easier in Windows 7 than it was in Vista, by adding to Win7 the Registry byte change that I mentioned above. The technique in Vista usually required a second install to work. Win7, thanks to changes deliberately added by Microsoft, usually doesn’t require that the setup routine be started twice.

Microsoft’s Windows 7 End-User License Agreement (EULA), however, says you can install an upgrade edition of Win7 only if you had a license for an earlier version of Windows that you’re eradicating.

It’s curious why Microsoft makes it so easy for customers to install an “upgrade” copy of Windows 7 on a PC that supposedly doesn’t qualify. Indeed, why has Microsoft built hooks into the Windows installer to specifically bypass the qualification test — hooks that have been left in place for years?

In any event, the relevant clause in the Win7 EULA says:

“To use upgrade software, you must first be licensed for the software that is eligible for the upgrade. Upon upgrade, this agreement takes the place of the agreement for the software you upgraded from. After you upgrade, you may no longer use the software you upgraded from.”

By that standard, the number of machines that don’t qualify for upgrade pricing is mighty tiny. (It also raises disturbing questions about multiboot systems, but I’ll discuss multibooting in a future column.)

For example, if you own a computer with a Windows Certificate of Authenticity sticker on the case as proof of ownership — and the certificate is for Vista or XP — there’s no question whatsoever that the PC qualifies for upgrade pricing.

If you’ve ever paid for a full copy of Windows — one you purchased “off the shelf,” not a copy that was preinstalled on a PC — you own the right to use that copy of Windows on any PC you like, as long as you use it on only one machine at a time. There’s no requirement that you activate it in order for a Win7 upgrade to work on it. How can that not be a legitimate candidate for a Windows 7 upgrade?

The universe of PCs that don’t qualify for upgrade pricing would seem to be limited to those that (1) have been built from scratch or (2) bear counterfeit builds Windows that unsuspecting customers bought from unscrupulous box shops. New virtual machines also require the full version, but that’s about it — this represents a very tiny slice of the consumer-PC pie. How do I know my Win7 installation is legit?

“If I can get an upgrade version of Windows 7 to install on my PC and it validates as ‘genuine,’ I’m running everything legally and don’t need to worry about it, right?”

As far as I can tell, if you pass the validation hurdle once with an upgrade version of Windows 7, your computer won’t have to do anything in the future to prove whether you were or were not entitled to an upgrade.

You’ll definitely be running a copy of Win7 that’s validated as genuine. Whether that also means your new copy meets the written definition in Microsoft’s EULA depends on whether you ever owned a legal copy of Windows for that PC. That can sometimes be hard to verify. Can I upgrade in place from XP to Vista to Win7?

“I’m running Windows XP. I know I can’t do an in-place upgrade from XP to Windows 7, but can I do an in-place upgrade from XP to Vista, and then another from Vista to Windows 7?”

You can, but that gives Windows two opportunities to shoot you in the foot.

Many of my friends tell me I’m superstitious, but I strongly recommend that people perform a custom (clean) install. Yes, that entails reinstalling programs and re-entering your custom system settings, but it’s still my advice — even if you have a PC that can accommodate an in-place upgrade.

Sticking Win7 on top of an old copy of Windows is like building a new house on old landfill. You never know what’s going to come to the surface, or where, or when. A very large percentage of the problems people are having with Windows 7 installations occur with in-place upgrades.

Which Win7 is right for me: 32-bit or 64-bit?

“Should I install the 32-bit or 64-bit version of Windows 7? How do I get the right one?”

Every Windows 7 box that you buy on store shelves — whether an upgrade or full version of Home Premium, Professional, or Ultimate — contains two DVDs. One has the 32-bit version and the other has the 64-bit version.

If you ignore the recommendation I made in the above item and insist on performing an in-place upgrade, you can do so only from 32-bit to 32-bit or 64-bit to 64-bit. However, if you do a custom (clean) install on a machine that formerly ran a 32-bit version of XP or Vista, you should seriously consider moving to 64-bit computing.

See my July 16 Top Story for information that will help you determine whether 64-bit is right for you. If you decide that it is, follow the instructions in the article to run the Windows 7 Upgrade Advisor.

If the Upgrade Advisor indicates your PC can support a 64-bit version of Windows — and it doesn’t warn you that your specific hardware doesn’t have drivers — give 64-bit a try. Although there are some devices from major manufacturers that don’t have 64-bit drivers, several of these vendors have been embarrassed into writing new ones. Can I upgrade Vista Ultimate to any Win7 flavor?

“I got suckered into paying for Windows Vista Ultimate. What a waste! Adding insult to pecuniary injury, if I want to upgrade, I have to pay for Windows 7 Ultimate, right?”

Nope.

If you want to perform an in-place upgrade from 32-bit Vista Ultimate, you have to pay for the Windows 7 Ultimate upgrade and must install the 32-bit version. However, if you perform a custom (clean) install, you can upgrade that Vista Ultimate PC to whichever version of Windows 7 you prefer.

It gets confusing because the term “upgrade” has two completely different meanings. If you want to do an in-place upgrade and avoid reinstalling your programs and updating your settings, you have very limited choices about which versions of Windows you can start with and what you can upgrade to. (See Microsoft’s somewhat-muddled explanation of the Win7 Upgrade Option Program on the official Windows 7 site.)

If you’re willing to perform a clean install, you can upgrade any version of XP or Vista to any version of Windows 7, and you need pay for only the Upgrade Option for Windows 7 — no need to buy the full-install package.

I just saved you about a hundred bucks, yes? The Windows 7 Q&A parade has just begun This is a small sample of the myriad Win7 questions that have hit my inbox. Some people are having problems with installations that go part way through and freeze. Others see the installation fail, then automatically try again repeatedly.

There are more than a few blue screens running around, and some of you can’t find your games after a Win7 upgrade. I’ll be covering these and many more problems in future columns.

I think Microsoft’s biggest mistakes with Windows 7 are the confusing number of versions and upgrade paths, as well as the complete dearth of technical information about the upgrade-validation process.

About Woody Leonhard

Woody Leonhard is a Windows Secrets senior editor and a senior contributing editor at InfoWorld. His latest book, the comprehensive 1,080-page Windows 8 All-In-One For Dummies, delves into all the Win8 nooks and crannies. His many writings tell it like it is — whether Microsoft likes it or not.

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